The announcement was made during a visit to Abbey Wood

The Defence Procurement Agency (DPA) and the Defence Logistics Organisation (DLO) will operate as one body.

It will be based in three sites in Bristol and Bath, and will see 2,000 existing posts moving to the area from sites across the south of England.

But union leaders attacked the relocation plans and warned of possible industrial action.

It represents a triple whammy for staff who face losing their job, having to move to another part of the country or yet more privatisation Mark Serwatka, General secretary PCSU

The Public and Commercial Services Union (PCS) and defence union Prospect pledged to fight the plans which they warned would force skilled staff to leave the civil service.

"Our members at these sites do not want to be forced to transfer to the South West and many will leave the MoD rather than move their families," said Prospect national officer Steve Jary.

The PCS said the plans were being "forced through" with little consultation.

General secretary Mark Serwatka said: "The lack of consultation over these plans has been disgraceful and represents a triple whammy for staff who face losing their job, having to move to another part of the country or yet more privatisation.

Armed Forces Minister Adam Ingram made the announcement during a visit to the MoD's Abbey Wood in north Bristol on Monday.

All DLO workers currently located at Andover South in Hampshire, Sapphire House in Telford, Shropshire, RAF Brampton in Cambridgeshire, Caversfield in Oxfordshire and Sherborne in Dorset, will be relocated to the South West.

'Appropriate support'

Numbers will also be reduced at RAF Wyton in Huntingdon, Cambridgeshire.

"I understand these decisions will impact on employees and their families and we will provide appropriate support for those affected," Mr Ingram said.

"That said, we owe it to our service men and women to modernise the support we provide to the Armed Forces to ensure resources are directed at the front line.

"These changes are an essential part of that strategy and will be subject to formal trade union consultation."

The merger is part of an on-going efficiency drive, which will see 10,000 job cuts within the MoD.

Ministers hope to save �200m over the next 25 years through the reorganisation.

The DLO site being vacated in Andover South has been named as the preferred site for the new HQ Land Forces headquarters, while RAF Wyton will become home to staff at RAF Brampton who are not affected by the move.